Emerson Process Management Series 9110, CI-9110, 9110-00A Transients and Interference

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the equipment. Wiring from input signal circuits and power circuits should be separated as much as possible to minimize noise and transient pickup. Power and signal leads should be run in separate conduit to minimize inductive pickup.

oTerminal Lugs. The use of crimp-type terminal lugs as connections for screw terminals should be avoided. Terminal lugs, in many industrial climates, can be affected by hidden corrosion. It is preferable to tin the wire end with solder and loop it around the terminal screw. The screw should be tightened sufficiently to hold the lead in place but not excessively so that the lead is sheared or the screw is stripped. Equipment furnished with compression-type terminals include an opening for inserting tinned ends.

TRANSIENTS AND INTERFERENCE

The extensive use of low-power integrated circuitry in modern electronic equipment requires proper grounding techniques to insure reliable system operation. The following checklist will help identify some critical areas:

1.All instrumentation devices at the site should be checked so that no potential greater than the standoff voltage can exist within or between devices.

2.To minimize outside signal interference and provide equipment protection from lightning or transients, the earth ground at the site must be tested to insure that its impedance measures less than 10 ohms at 7 MHz. This qualification is essential since a transient potential or an interference signal at the instrument site can vary over the entire electromagnetic spectrum from DC to several hundred MHz.

Note that transients can be produced through natural phenomena and man-made conditions. Natural transients may result from lightning (7-14 MHz), static (many frequencies), and wind (DC charge and static). Man-made transients can result from defective light bulbs or electrical appliances, sudden electrical load shifts, inductive load surges, arcing contacts and poor AC power connections.

3.If radio frequency (RF) interference is present at the input of an instrument, observe if it has a consistent or irregular pattern. Constant interference can come from commercial radio stations, while irregular interference can come from private stations. Although shielding and grounding will eliminate or minimize most cases of RF interference, obstinate cases may require attenuation filters.

RF interference can also be caused by power companies that apply modulated RF signals to power lines to communicate data. Other RF noise sources include digital clocks, computers, relay contacts, motors transformers, switches, arc welders, etc.

Supplement S1400 / 5

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Contents Remote Set Regulator Model 9110-00A IMPORTANT! Read Instructions Before Starting Warranty Mail Bristol IncPhone Bristol Inc. Repair Authorization Form off-line completion Training 860 860 945-2213 FAX Telephone Support Technical QuestionsVisit our Site on the World Wide Web Training Courses Model 9110-00A Remote SET Regulator Supplemental Instructions Product Description Theory of OperationAnalog Regulator Model Remote Set Regulator Block Diagram of Analog Type Regulator Current Output Guard InputBlock Diagram of Raise/Lower Type Regulator Data Plate Raise/Lower Regulator ModelModel Number Breakdown = Pneumatic Output = Mounting Arrangement Page In-Line Mounting GeneralMounting Two-Inch Pipe MountingGeneral Piping Pressure ConnectionsMoisture in Lines Regulator AssemblyBody and Cover Internal AccessLine Size VentingElectrical Conduit Port Safety NotePage Using Option Switches Cradle Switches with Open DesignationSlide Switches with on Designation RAISE/LOWER Input Models Switch FunctionsRegulator Assembly Switch SW1 & SW2 Functions & Settings Analog Input ModelsIncremental Signal Continuous SignalInput Filter Switch SW1 1-5, Pulse IncrementsGuard Logic Guard InputOutput Rate of Change Static or Dynamic Guard InputAnalog Failure Modes Fail Hold & Fail Zero Switch SW2 2-5, Output Rate Of ChangeFAIL-ZERO Mode Page Field Wiring Terminal Identification For Raise/Lower Models Terminal Identification For Analog Input ModelsAnalog Voltage Input with Guard RAISE/LOWER Inputs with Guard Analog Current Input 4-20 mA with GuardRaise/Lower & Guard Inputs from Relay Contacts Current Output to FSK Bi-State Transmitter DC PowerInitial Checks Operating NotesField Wiring CI-9110 Service Troubleshooting Hints General Principles Setting Output LimitsTest Setup ProcedureCalibration Precaution Calibration Test SetupPreliminary Calibration Check Analog Test SetupPressure Output Check Detailed Calibration for Analog ModelFeedback Zero & Span Current Output Span & LoadDetailed Calibration for RAISE/LOWER Model Raise/Lower Test SetupCPU Board & Termination Board Reference Table PCB Reference DrawingsAssembly, Analog Type CPU Board with Current Output Assembly, Raise/Lower Type CPU Board with Current Output RAISE/LOWER Input Model Analog Input ModelStepper Drive Mechanism Analog OutputAccuracy Analog Models Accuracy RAISE/LOWER ModelsRange Factory Calibrated with Pressure Regulator AssemblyInstrument Enclosure EnvironmentalHumidity 10 to 95% over -20to +130 F -29to +55 Range Parts Referenced in Figure Model 9110 Main PartsRemote Set Regulator Actuator Unit Remote Set Regulator Actuator Unit Mounting Parts Remote SET Regulator Basic Parts Remote Set Regulator Assembly Basic PartsGuidelines for System Grounding Basic Ground Rod Installation General Recommendations Noise and Signal ErrorsGrounding of Equipment Housing Transients and Interference Grounding of Transmitter Types of Earth Grounds AC Power Grounding System Dry Soil Sandy SoilRocky Soil Following installation procedures apply Several DPCs Mounted in Metal Cabinet with Power SupplyGrounding for DPCs and Power Supplies Single Metal Cabinet Multiple DPC Cabinets Powered by Single Power Supply Elements of a Facility Ground System References Multiple Clusters of DPC Cabinets Powered by Local SuppliesPage Remote Set Regulator Model 9110-00A
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